1. Field of the Invention
The present invention relates to a combined functional and decorative exhaust system for motorcycles and similar two wheeled internal combustion driven motor vehicles. More particularly it relates to a rotating motorcycle exhaust pipe that may add dynamic and artistic appearance and may act as a hot exhaust gas heat dissipater, as well as an eye-catching safety feature that will, in some instances, make automobile drivers more readily aware of the presence of a motorcycle, especially at crossings. Thus, the present invention includes a first, fixed pipe and a second, rotating pipe rotatably connected to the first pipe, and a drive mechanism to rotate the second pipe. The term “exhaust pipe” and the term “tail pipe” may be considered different by some technicians, but are used herein interchangeably because, for purposes of this invention, any technical differences between the two are irrelevant.
2. Information Disclosure Statement
The following patents are representative of prior art of interest to the present invention technology:
U.S. Pat. No. 5,579,638 describes an adjustable exhaust system for use with two cycle motors. An insert section of pipe is interposed between a header pipe and a conventional tail pipe so that, when it is rotated, the overall length of the exhaust system is adjusted. The insert section is held in place between the tail pipe and a header extension pipe by a compressive force exerted by one or more springs attached between the header and the tail pipe. The insert features, on an end that slips over the header extension section, a series of graduated notches which mate with a protrusion, or “stop”, formed on the mating end of a header extension section. This notch and stop combination determines the distance by which the insert section will be permitted to slip over the header extension section, and correspondingly, the overall length of the exhaust system.
U.S. Pat. No. 5,058,704 describes an improved muffler including a body with an exhaust inlet in the form of a porous pipe enclosed in a second porous pipe for diffusing exhaust gases into the interior of body. A pair of pipes introduces ambient air into the discharge region of the muffler. A constricted discharge opening of the body encircles the pipes and confines the helical vanes which impart a helical path to the exhaust gases just before mixing with ambient air from the pipes. A venture section with a bell shape outlet completes the tail pipe section. An auxiliary air inlet to the venture adds additional ambient air to the final outlet via ports. In addition embodiment, the venture section is within the muffler body. A constricted tube provides a direct path for a portion of the exhaust gases while the major quantity of exhaust gases traverse the helical paths defined by the vanes.
U.S. Pat. No. 5,058,703 describes an exhaust to reduce noise, an automotive exhaust tailpipe that has a convoluted surface at or near its outlet to generate pairs of counterrotating axial vortices within the exhaust gases just before or just after the gases exit the tailpipe. The convoluted surface of the tailpipe, or a thin-walled convoluted member, may be disposed within the tailpipe near its outlet end.
U.S. Pat. No. 4,860,538 describes several embodiments of motorcycle exhaust systems having forward and rearward exhaust pipes at least one of which extends transversely in a transversely extending expansion chamber for improving high speed performance. In addition, a variety of control valves are incorporated for varying the reflective area of the exhaust pipe ends so as to improve low speed and midrange performance.
U.S. Pat. No. 4,220,219 describes a lightweight muffler and method for muffling a noise component of a stream of gases. The muffler includes a chamber in which gases are directed side-by-side streams flowing in opposite directions. The streams are in contact with each other for the generation of sound dampening eddy currents in the chamber, but such contact does not break down the continuous, low resistance flow of gases through the muffler. The chamber is advantageously formed as a expansion chamber in which gases: enter one end of the chamber as an annular stream concentric with the inlet pipe to the muffler, travel along the inlet pipe to the other end of the chamber, are reversed, and travel as a concentric annular stream of greater diameter in the opposite direction down the length of the chamber for discharge into a passageway leading to the outlet tube to the muffler. A second similarly formed chamber for counterflow of opposed streams and the generation of eddy current there between is preferably formed proximate the outlet tube of the muffler.
Notwithstanding the prior art, the present invention is neither taught nor rendered obvious thereby.